The present invention relates to an auditory jack which includes a casing protected inside a metal shell and having an internally threaded metal socket extended out of the metal shell through a hole for receiving the plug of an audio output device, an inside space divided into a plurality of troughs by a plurality of projecting blocks, into which two movable terminals and two fixed terminals are respective inserted, and a plurality of columns respectively made inside each trough and fitted into a respective round hole on a cover for permitting the cover to be firmly retained to the casing, wherein the movable terminals and the fixed terminals each has an end formed into a respective angle strip inserted into a respective groove on the cover and retained in place. Threading the plug of an audio output device into the metal socket causes the movable terminals to be disconnected from the fixed terminals. The movable terminals each is respectively formed into a triangular configuration which allows the size of the jack to be greatly reduced and provides a springy material property for electrically connecting the plug being threaded into the metal socket and for permitting the respective movable terminal to be able to return to the respective former shape after being pressed by the plug. Therefore, the problem of contact failure is eliminated, and a high transmission quality is achieved.
An auditory jack is a plug-in receptacle on an audio equipment used to make electrical contact. FIG. 4 illustrates an auditory jack according to the prior art in which two contact plates (61) are fastened inside a casing (6) at two opposite locations. The contact plates (61) each has one end bent inward and a curved springy strip (62) extended from the respective middle part. The curved springy strip (62) of each contact plate (61) is connected to a respective conductor (63). The casing (6) has an externally threaded socket (64) at one end fastened with an internally threaded sleeve (65). The sleeve (65) has two opposite mounting plates (66) respectively fastened to two opposite columns (67) inside the casing (6) and two spring strips (68) separated by the mounting plates (66). As the outer connecting end (71) of the plug (7) of an audio output device is inserted through the socket (64) into the casing (6), the curved springy strip (62) of each contact plate (61) is respectively squeezed outward, and therefore the output signal of the audio equipment is sent through the curved springy strip (62) of each contact plate (61) to the audio output device through the plug (7). The main disadvantage of this structure of auditory jack is its big size. Because the curved springy strip (62) of each contact plate (61) is squeezed by the plug (7) as the plug (7) was inserted into the socket (64), the curved springy strip (62) must be made in a suitable length so that a positive contact with the plug (7) can be achieved. If the size of the curved springy strip (62) is greatly reduced, the problem of elastic fatigue may occur easily causing a contact failure.